Bass Test
A bass test for speakers, subwoofers and headphones: play steady low tones, sweep down to find the lowest note your system plays, and track down rattles.
Turn your device volume down first.
Start quiet. Turn your device volume down before you play anything, then raise it slowly.
That is a high setting. Lower it before low or high tones, and never raise it with headphones on your ears.
How to use the bass test
Before the first sound this bass test asks you to turn your device volume down, then press Play in the warning. Under Low tones, press a frequency from 120 Hz down to 20 Hz to play a steady sine tone on both channels; press it again to stop. Start low sweep glides from 120 Hz down to 20 Hz in 40 seconds; press I cannot hear it any more when it fades out and the tool shows the frequency. Rattle check sweeps slowly up from 20 Hz to 200 Hz; press Mark a rattle each time something buzzes.
Keyboard: Space marks the running sweep, Esc stops everything. The Stop button and leaving the page also stop the sound.
Play it safe
Low tones can be loud on a subwoofer and can rattle or damage small speakers. Start with the volume low and raise it in small steps. Stop at once if you hear distortion, flapping, clicking or a hard knocking sound: that is the speaker reaching its limit, not more bass. With headphones, raise the volume before you put them on, never with them on your ears.
Subwoofer test and the LFE channel
The low-frequency effects (LFE) channel, the ".1" in 5.1, carries deep effects in the 3 to 120 Hz range. A subwoofer can also play bass taken from the other channels: a receiver's bass management sends the low part of every channel to the speakers that can handle it. This page plays its tones on the left and right channels, so with bass management on, the subwoofer plays them too. To fire the LFE channel by itself, use the surround sound test on a system with 6 or more output channels.
If the subwoofer stays silent, check that it has power and its own volume is up, and that your TV or receiver is set up to use a subwoofer.
Reading the low frequency test
The frequency where the sweep fades out is about the lowest note your speakers play at that volume. Run it twice to check, and repeat on another set of speakers to compare. For reference, these are the lowest notes of common instruments:
| Note | Frequency | Where you meet it |
|---|---|---|
| A0 | 27.50 Hz | lowest key on an 88-key piano |
| B0 | 30.87 Hz | low B string of a 5-string bass |
| E1 | 41.20 Hz | low E string of a 4-string bass |
| A1 | 55.00 Hz | A string of a bass |
| E2 | 82.41 Hz | low E string of a guitar |
If your speakers fade out above about 41 Hz, the lowest string of a bass guitar will sound weaker than its higher notes. A rattle that you marked can be found again by playing the nearest fixed tone, or any exact frequency on the tone generator, while you touch shelves, panels and the grille. For the rest of the range, run the sweep on the speaker test.
More for sound check: Mic Test · Sound Test · Speaker Test · Headphone Test · Left Right Test · Surround Sound Test · Audio Delay Test · Speaker Cleaner · Tone Generator
Questions
Can a bass test damage my speakers?
It can if the volume is too high. Start low, raise slowly, and stop at the first distortion or knocking.
Why can I not hear 20 Hz?
Many speakers cannot play that low, and 20 Hz is the bottom of the commonly stated range of human hearing, 20 Hz to 20,000 Hz.
Does the bass test work with headphones?
Yes. Set the volume low before you put them on. Each pair of headphones and speakers gives its own result, so compare them at the same volume.
Why does my subwoofer not play the tones?
Check its power, its own volume knob, and that the TV or receiver sends bass to it. On a stereo setup without bass management, the subwoofer may need its own cable from the amplifier.